


And may the seas hear our oath

by TJ_Writes



Category: One Piece
Genre: Alternate Universe - Canon Divergence, Alternate Universe - Fantasy, Canon-Typical Violence, Follows canon fairly closely to be honest, M/M, Other Additional Tags to Be Added, The Author Regrets Everything
Language: English
Status: In-Progress
Published: 2017-07-11
Updated: 2017-07-14
Packaged: 2018-11-30 21:59:17
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 4,902
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11472510
Author URL: https://archiveofourown.org/users/TJ_Writes/pseuds/TJ_Writes
Summary: A young demon sets out on a journey to achieve his dream.Along the way he experiences the joy of friendship, the intensity of trust, the pain of sorrow, pride in the face of unbreakable loyalty and perhaps the warmth of affection.





	1. Chapter 1

**Author's Note:**

> Written for the first [Zolu week 2017](http://zolu-week.tumblr.com/) prompt: Fantasy AU
> 
> This is the start of a self-indulgent multi-chapter AU that quite simply was born out of my own petulance and nothing else.
> 
> It is also turning out way too long and regarding actually ever finishing this monster... I make no promises.

 

It is said that demons were not originally part of the mortal world, that the gates to the pits split the surface millennia ago in a cataclysmic event that sent clouds of ash into the skies and liquid fire pouring forth from great wounds in the landscape.

Angered by the unnatural birth of new islands and landmasses, the ocean itself rose to challenge the unbalanced existence; bringing forth waves as high as the rising mountains and spinning whirlpools to swallow up anything in their path.

The raging war would eventually come to peter out, leaving only the curse of the seas as a reminder; no demon would ever be welcome on the vast blue waters.

None of that bothers Luffy. He made a promise years ago, and it was one he intended to keep no matter the temperamental ocean he would have to cross to do so. Predictably, a loud chorus of incredulity and dismay is what follows his announcement of setting out on his very own journey across the seas. _‘Stupid kid, you can’t even swim!’_ and _‘Why would a demon become a pirate?’_ follows him even to the shore - the beginning of adventure - but there is also acceptance and teary farewells hidden in the actions of his human caregivers and the familiar townsfolk.

Luffy leaves the village of Foosha in a small dinghy, stomach full of butterflies and with a great big grin on his face. It is a feeling he wouldn’t change for the world - the feeling of anticipation, excitement and freedom.

 

 

A timid and panicky human is the first friend he makes, only a few days after leaving the village. He had underestimated the ire of the ocean and got caught up in a large whirlpool, which he hid from in a barrel that was then picked up by the boy. Coby is what he calls himself and he cowers just at the mention of reaching for his dream. Luffy can’t make any sense of the human but he makes short work of the rude pirate Coby had been so terrified of anyway because there’s a strong will somewhere under all that anxiety. After regaining his freedom the human seems willing to try harder, though not before losing his mind over Luffy’s demonic origin. Nothing seems to be simple and straightforward in Coby’s world.

An island nearby hosts a Marine base - a place they set their course for together, though for entirely different reasons. Coby wishes to enroll in the ranks of the marines and Luffy is interested in seeking out a rumored prisoner; one certain character who for some curious reason has earned the monikers _monster_ and _devil_ while hunting pirates of all things. ( _Hunting the lawless shouldn’t make people fear you, right?)_

On approach the garrison looms tall and uninviting above everything, massive cannons lining the buildings and covering all directions of approach and _escape_.

Undaunted by the oppressive air blanketing the base, Luffy traipses down along the stony wall to avoid being hammered by the raw emotional disaster next to him - _how one human can produce that much jitters is beyond him_ \- and to get a feel for something he is much more interested in. Something that has been agitating his senses since their moving into range of the fortified buildings.

Now, the further he walks along the wall the stronger the feeling gets - a strange presence of some sort - and the hairs on the nape of his neck stand on end. It is definitely something new and if Luffy isn’t reading it completely wrong, his body actually seems to be telling him to _stay away_. And that isn’t just curious, but also _very exciting._

Single-minded in his search, Luffy climbs the wall even as Coby yelps at him, scrabbles up the smooth tiles with the claws that pop out of the tips of his fingers, hauls himself onto the edge the moment his hands find purchase. A wall of smells hits him the face (blood, death, decay, gunpowder, metal, _agony_ ) and he squints through it all.

A severely battered man stands there, in the middle of the dry and dusty courtyard under a particularly unforgiving midday sun. _Standing_ is not quite the right word either, as he seems to favor hanging slumped in the copious amounts of ropes used to tie him to a cross-shaped post. Though seemingly unresponsive the man is definitely still alive because the intensely heavy and hostile aura that lashes out against Luffy’s curiosity is nothing if not spirited. Maybe that is the reason why Coby falls off the wall the moment he dares to peek over the edge. Luffy is too distracted to ask; not only has he apparently found the _‘monster’_ but he is also almost sure that it is the pirate hunter who is the source of the odd presence that reeled him in.

Slowly, jeering, the hunter lifts his head to sneer at them, curling his cracked, bleeding lip like an animal. Despite the angry rope burn visible on his arms, his sunburnt, flaking skin and the apparent exhaustion, Roronoa Zoro meets Luffy’s gaze head on and the resulting nearly audible snap of static in the air reaches all the way to one’s very _bones_. Luffy no longer has any doubts.

 

 

The pirate hunter himself does not have much to say, wearing his stubborn pride on his sleeve but not giving any clues to his motivations. There is a weight to his words and he is adamant about a goal (a _dream_ ) to the point that the evident starvation and torture he has been through appears to not worry him, at least not visibly.

A tiny little girl in her striped dress is the key to the mystery of the bound prisoner. At the wrong place at the wrong time - or perhaps at the right place at the right time - under all that bluster and bark Roronoa Zoro turns out to be a surprisingly benign force of nature; dangerous and unpredictable yet prepared to risk his own well-being when faced with terrible injustice.

To have such a strong will betrayed, made out as a fool by some arrogant shirk makes Luffy’s blood boil in a way he is fairly certain he has not experienced before. _How dare they._

It is clear as day then; it is his first crewmate strung up in that awful courtyard and that is a wrong that needs to be righted immediately.

 

 

The barren courtyard is the same as before ( _hot, dry as bone, suffocating_ ) and so is the lone prisoner.

“I will not be a pirate!” Zoro has not crumbled under fatigue nor the elements and though his voice is hoarse and unsteady he still manages to put up a fit of incredulous outrage.

The hunter is stubborn, but so is Luffy who refuses to budge on his decision. “You are a swordsman right? Did someone take your sword? What if I get it back for you?” He tries, picking another approach when badgering doesn’t seem to do any good. Not everyone is on the same level of straightforwardness after all.

Zoro simply glares from under the dark bandana that has probably been his only saving grace, shielding his head at least partially from the harsh sun. He looks close to offended, definitely aggravated. “Are you... Trying to _extort me right now_.”

Luffy cocks his head to the side, thoughtful. “Well, I guess I could? But it would be a lot easier if you just said ‘okay’ instead.” He does not believe it would be an easy task to perform, and the thought of a crewmate who harbors resentment towards him doesn’t sound very tempting. He would much rather make friends.

The rough ropes that trap the pirate hunter are tight and unforgiving, digging into already bruised and damaged skin when Zoro strains angrily but helplessly against his restraints. Luffy frowns as he watches the other slump exhausted against the post again, blood-stained teeth glinting in a barely-there grimace of agony. “Just _leave_ already.” Zoro groans wearily as if all fight had left him in the one struggle.

It is clear then that the missing blade is important; persistent refusals forgotten and replaced with unrestrained anger and a slightest waver in steadfast attitude. Perhaps a show of good will might sway the other further, Luffy wonders (or perhaps dares _hope)_. After all, it is his duty as captain to see to his crewmates dreams and hopes, to help them with the burdens they may carry. Without crew, there is no captain. If the sword is important to Zoro – _important like the frayed hat of straw that Luffy values over all treasure in the world_ – then by extension it is important to Luffy as well.

There are no further decisions to be made and he sets off towards the closest garrison tower, sandals slapping over dirt as he goes. “Okay! I’ll go get your sword - swordsman pirate sounds really cool!”

He doesn’t slow to wait for a reply and the confused bellow of ‘ _What? Hey!_ ’ gets left far behind in the dusty courtyard as Luffy flings a hand to the top of the tower, stretching his rubbering arm the entire way to slingshot himself up and up and _up_.

 

 

Not much resistance is found inside the metal-coated garrison and locating his would-be charge is made easy with the unwilling aid of the sword thief himself. There is one small problem; instead of one blade, three are propped up against a wall, displayed as some kind of undeserved trophy under a wall-mounted crest. Pure instinct is tells Luffy he doesn’t have a lot of time so he makes to grab all three - the owner will definitely know.

Two plain dark hilts have nothing to say to the demon grasping them, but the lone decorated white one carries quite the personality and Luffy yelps in surprise when the ornery blade gives him a freezing cold shock that travels up his entire arm, stopping only when the sword is released from his grip. ( _Huh, that’s weird. Better carry that one between the others.)_

Trusting his instincts is something he learned very young and it proves useful once more as Luffy plummets from the higher levels of the garrison, landing just in time to catch the bullets aimed for his far more vulnerable friends (Coby is there too, bleeding and terrified but also furious). Luffy laughs through the incredulous and horrified shouts aimed at him and the unmarred rubbery flesh that stretches out behind him for a brief moment before it snaps back, spitting the now harmless metal to the ground.

Finally free, Zoro hits the courtyard with an audible _snarl_ and stops the charge of an entire troop of marines. It is quite the sight; chest heaving from the sudden exertion, the swordsman holds off the row of blades with his own - three blades used in unison and one of them between gritted, bloody _teeth_.

The cruel and feared marine lieutenant Morgan is a giant of a man with a metal jaw and an enormous axe for an arm. His arrogant, sniveling son is no more than a spineless nuisance.

Neither is a match for them - the coward cannot hope to withstand a far-slung jaw shattering punch and Morgan felled by the fast and ruthless slash of swords. For all his complaints, Zoro throws himself into his new role with abandon and Luffy feels so very right in his choice to trust.

Coby’s eyes light up when the remaining marines loudly declare the deranged lieutenant a traitor and a fiend to be brought before justice. Luffy wonders just what kind of marines they were to keep their silence for so long but chooses to keep that to himself for the sake of his human friend. Instead, he ignores the ruckus and turns to Zoro, curious of what the swordsman would think of it all.

Zoro says nothing at all and his eyes - what is visible of them under the bandana and all the dried blood - lack the ferocious glint from before. He sheathes all three swords carefully and then falls forward, collapsing onto the ground.

 

 

Exhaustion, dehydration and malnourishment is what the doctor announces after checking over the swordsman. Considering the circumstances, that is supposedly a lucky sentence - normally the situation should have been much worse. Luffy doesn’t believe it has anything to do with luck; he has experienced just how stubborn his first crewmate is.

They are set up in the small cozy inn that is owned by the mother of little girl in the striped dress. Humbled and thankful, the woman had immediately offered them room and board before sending her daughter to fetch the local doctor.

Said doctor gives an estimate of _days_ Zoro would be bedridden, only awake for short periods of time, just enough to get some food in him.

Nearly everyone is surprised (Luffy chuckles pleased and _proud_ ) when Zoro wakes a few hours later, disoriented, shaky and feverishly sweaty but definitely aware. Soup is brought before him and he forces it down before raspily excusing himself, stumbling off towards the offered washroom and nearly tripping on his own feet as he goes.

Luffy really hopes his first crewmate doesn’t drown in the bath. That would be a real downer after all the excitement earlier.

Zoro spends quite some time in the washroom but when he finally reappears he no longer looks ready to fall over at any moment. The shivers are gone. Some healthy color has returned to his skin and he has the energy to snap at Luffy ( _‘Close your damn mouth your drink is escaping!’_ ) who is absolutely mesmerized by the now clean _meadow green_ hair that tops the swordsman’s crown.

The innkeeper serves them a hearty meal for the evening, assuring them they are no bother and invites them to stay for a while even if Zoro does not need full bed rest. (It is strange really, Luffy thinks as he watches his crewmate, he could have sworn the other had more wounds on his face earlier and that his rope burn was far more irritable and bleeding.)

 

 

Two days later they say some hasty goodbyes and set off just the two of them. Their last dinner in the inn interrupted by a troop of marines now citing they had to follow rules and couldn’t let pirates roam free in the village. Though finding it all very amusing as he recalls just how well the marines had been protecting the townsfolk from their own lieutenant before, Luffy holds his tongue. Coby has finally found his place and he would never ruin that for his human friend.

Zoro seems unimpressed by the whole ordeal, a look that Luffy has already been on the receiving end on several times over the past few days. It turns out his first crewmate isn’t much of a talker, preferring instead to grunt and huff when prompted for conversation or an answer. Zoro mostly speaks up when he is irritated or angry, like when Luffy had asked him of his origin _(‘So what are you really? Ocean spirit? River being?’_ ) and then not stopped needling him about it _(‘Are you sure you’re human? Your energy felt really weird at first and the sea hates me. Also, your hair is really green.’_ ) until the swordsman lost his temper and whapped his captain across the head with a sword hilt.

They spend the next few days learning to navigate _each other_ \- any actual sense of direction is severely lacking between the two of them (Zoro takes the prize, unable to tell left from right at times) and so the seemingly simple task of locating the next town becomes a real challenge.

There is the issue of going out to sea but lacking the means to do so. Having always flung himself into the open arms of luck, Luffy has no plans and no direction, content to let adventure take him where he is supposed to be. He is overjoyed to find that Zoro - who first had grumbled about _‘some pirate crew this is’_ \- has a rather similar outlook on things, having wandered from place to place in his search, turning to bounty hunting to make ends meet.

(It doesn’t get them very far on their journey but at least they don’t fight.)

**Notes for the Chapter:**

> I do love comments, so maybe leave one if ya like?
> 
> For anyone interested; you can find me on tumblr [here.](http://rokudo-no-tsuji.tumblr.com/)


	2. Chapter 2

Fate is not a concept Luffy believes in. The belief that every adventure, every decision, every great stroke of luck is simply a rigid foretold occurrence without chances taken and odds overcome.

It is such a depressing, dull ideology.

Chance, coincidence and pure luck is what he embraces, the need to _live by it_ only strengthened by the chaotic soul within - the natural demonic calling to upset the balance of things, to break every chain of restrictive tradition.

Occasionally, the willingness to throw his dice at any odds does get him into trouble.

Through some unfortunate circumstances involving a bounty on a lesser gryphon that turned out to be a greater gryphon (and Luffy failing to pay much attention to the warning given by the suspicious swordsman at his side) the crew of two is suddenly split up.

The feathered, shrieking fury carries its demonic assailant into the skies and Luffy does not dare fight the creature that rounds the coastline, constantly swaying back and forth over land and sea. He digs his hands into the prickly plumage and resigns to waiting for a safer area to drop down.

 

A small town by the sea is where he finally disentangles himself from massive claws and drops like a rock. The same strangely desolate town is where he meets his next crewmember; a witchling with a serious knack for trickery, a great love for riches and a unwavering confidence in her ability to navigate the most unpredictable seas.

(Sometimes chance is a fickle, mysterious thing.)

Nami is a character of smarts and cunning, both her rust red locks and the more unpleasant side of her personality reminding Luffy of a trickster fox. He finds himself unwittingly pulled into her games, not only lied to but also reduced to bait, brought before the crew of violent pirates that occupy the town.

Only at the very last moment - when she can no longer pretend nor lie herself out of the situation - do Nami’s true colors bloom through her carefully built and maintained guise. Luffy helplessly watches her desperation as she tries to right her wrong, to call forth powers the inexperienced witchling clearly never before has wielded so woefully unprepared. He forgives her in that moment, vowing silently to protect her from whoever taught her to _hate_ so strongly.

 

In the end it is Zoro who comes to their rescue, putting himself between them and the malicious crew. And then he _bleeds_.

The air is thick with the stench of warm blood and the feverish energy enveloping the swordsman pulses in time with every punishing blow, with every agonizing shift. Zoro growls through the pain and wields his own body as if it was _expendable_.

(He even feels different, Luffy realizes, this is not the unsettling static from before - this is strictly restrained _bloodlust_.)

When Luffy is finally free he wants nothing more than to make sure that the jeering mob of trash never so much as lay a finger on his crewmates ever again. Instead, he settles for obliterating the man the rabble of pirates call captain. The red-nosed menace holds the powers of a unsettling Devil’s fruit and his aura is equally off-putting. He proves his character to be that of _scum_ , immediately seeking out the person least capable of defending themselves against him.

Luffy puts and end to the bastard's reign of terror and takes great pleasure in doing so.

 

The townsfolk offer little help, understandably distrustful of pirates after being besieged by a crew for weeks. Entire rows of buildings have been leveled, homes destroyed.

When Nami offers him a share of the treasure she had found in the defeated pirate’s stash Luffy accepts it, only to sneak it into a secure but obvious enough spot for the townsfolk to find. They will need to rebuild after all, and he is sure that the valuables will help with the acquiring of materials.

(Nami very nearly shoves him into the sea once she finds out about the treasure. Zoro laughs.)

The blasted road through the town takes them down to the small harbor where Nami simply points to the two light sailboats tied to the pier. She claims one of the boats as her own and gestures to the other. “There’s no one here to anger and you need a boat to sail.”

Having left treasure for the town repairs, Luffy figures that a small boat going missing shouldn’t be much of an issue. Zoro is mostly draped over him, teetering on the edge of consciousness and likely unable to comment on the matter, but Luffy is fairly certain that the other wouldn’t have any complaints.

Once finally able to take a seat ( _slump_ into the sailboat like he was dead) and not focus all of his remaining strength on just keeping his knees from buckling, the swordsman seems to stabilize on the spot, scoffing at the suggestion he might need medical attention. A change of wound dressings is all Zoro wants, and he accepts the gauze and adhesive tape that Nami hands him, though not before showing his appreciation of her calling him a _‘freak of nature’_ by rolling up his bloodied shirt with a sound so sticky and soggy that the witchling shrieks at him.

Luffy laughs, delighted by the two spirited yet so different characters he has found. A skilled fighter to join him in battle, to share the burden of protecting precious and more vulnerable crewmates. A navigator to guide them across the raging, untamed seas.

Though one of them still has qualms about working with pirates - or even worse, _becoming a pirate_ \- Luffy knows she will come around eventually.

 

They set out on the ocean together, short on supplies, but now with a navigator on the crew drifting aimlessly for ages is no longer an issue to be worried about. Confident in her skill, Nami makes something incredibly challenging seem easy - or perhaps reading the sea and the skies just comes naturally to her.

 

Later, a uninhabited island offers a bounty of fruit, fresh water and a short relief from the neverending blue depths of the ocean.

“So you realize Zoro has a affinity for blood magic, don’t you?” Nami sounds faintly hesitant when she speaks, but not out of worry that the swordsman would wake at the mention of his name. It cannot be that, since by now they have both questioned and accepted Zoro’s ridiculous ability; the ability to sleep anywhere and at _any time_.

The hesitance must be about something else, that much Luffy realizes, though that is also where his insight ends and confusion starts. “Affawhatnow? Blood magic?”

Rapidly a storm brews in Nami’s gaze, her incredulity mixing with something akin to fury until the air around her aura takes on a foreboding scent - rain and dark skies. “You don’t know what a magical affinity is?!”

“Ahh no... Should I?” Luffy tries carefully, but ends up as the focus of the navigator’s wrath anyway.

“Should you. _Should you!_ I don’t even - !”

Nami does not find the words to continue her fit of outrage and shouts of frantic disbelief, instead she grabs him by the ear (it doesn’t hurt, but the _intent_ is there) and begins a lecture so long and complicated that by the end of it Luffy has considered burrowing into the sand beneath just to escape the barrage of knowledge and details.

Magical affinities, colors and tone of the soul, rituals of awakening, arcane transference, sigils, seals, runes - it all blends together into one great big jumble. The world holds so many different kinds of magic, one more powerful than the other - the next one more mysterious than both before it. Though amazed and awed by some, Luffy never bothered to study any of them, figuring he would experience and learn when he meets the variety of beings capable of bending the arcane arts to their wills.

_Blood magic_ was the starting point of the lecture, and though Nami approaches it carefully, her apprehension is apparent as she warns him of the effects of such a unconventional power (the power of your _own blood_ ); violence, bloodlust, chaos.

None of it worries a _demon_ much.

(And a demon is no stranger to undeserved wary first impressions and wrongly presumed cruel intention.)

As he struggles to make sense of it all, a familiar pattern starts to appear. Powers that depend on what the holder feels - physically or emotionally, the ability to withstand tremendous amounts of force, the _rapid healing factor_. “So it’s berserking? But pain instead of getting really angry?”

Why Nami couldn’t have just said so from the start and saved him the headache Luffy doesn’t know. It is as if the witchling detests helpful simplification. Judging by the face Nami pulls when faced with Luffy’s simple, straightforward summary, she might as well.

“...yes, blood magic is technically one of the berserker types.” She eventually admits sulkily, twisting her hands together as she refuses to meet the questioning gaze aimed at her.

“Ohh! That’s no problem. My grandpa is a angry berserker and Zoro is _so much_ nicer than gramps.” Luffy flops back down against the sand, wiggles and stretches out all the post-lecture tension and boredom out of his limbs. (If he ever has to go through all that again, it’ll be too soon.)

Nami mutters something but even the witchling seems to have had enough of magical theory for one night. She sighs, leans back against a large smooth stone and turns her face to the sky.

Luffy follows her example, but finds little wonder and inspiration in the hundreds of glimmering dots just then; he is much more absorbed by a amusing little detail that has been tittering at the back of his mind from the start.

“Ya know, it’s pretty funny that it’s Zoro you’re scared of and not me!”

“I never said anything about being _scared_ , I find his magical affinity gross.” Nami huffs at the implication of fear, her voice carrying a sardonic tone fitting for the eyeroll and _‘oh please’_ expression that likely has appeared on her freckled features. “As for you, you’ve just eaten a Devil’s fruit. It was weird first but not exactly rare.”

“I’m a real demon though.” Luffy chirps, kicking his legs up so his sandals go flying.

Impatience creeps back into the witchling’s voice, a warning to not _push_ lest another lecture would be wanted. “No you aren’t. Devil’s fruits don’t work on real demons.”

“Yeah! But I was born human, kinda? Ehhh I’ll just show you.” Luffy brushes his straw hat off, letting the precious gift rest safely on the sand as he sits up and feels his pupils constrict into thin slits.

It is a while since he has shifted fully and the tingly, itchy feeling of prickly, coarse hairs growing in inky waves across his limbs, his back, even his forehead - it makes him want to scratch all over, to ignore the claws protruding out of his fingertips. (The fur has always been the worst thing, second only to the feeling of growing a tail while wearing pants.)

“Show me wha-!?” Lacking all of the earlier impatience and vehemence, Nami’s voice turns into a shocked wail before she can finish speaking. Clambering nearly completely _backwards_ over her back rest, she loses her balance and tumbles over the rock, swearing.

Unconcerned by the navigator’s comical levels of sudden distress, Luffy reaches for his horns when they push out of his hairline, eager to feel if they’ve grown and if the left one has finally righted itself from a lopsided bend.

It hasn’t. Disappointed, Luffy groans and throws himself onto his stomach to roll across the beach in what surely comes across as a temper tantrum. He stops only just before bumping into Zoro, who true to character has been sleeping through the entire thing. (Does he really still need so much sleep when the wound is pretty much gone already?)

Nami is still behind the boulder, staring as if she has never seen a demon before. (She probably hasn’t.) “What are you doing?” Luffy huffs, still upset about his horn and not realizing he probably shouldn’t provoke the navigator.

Nami _erupts_ into another incredulous fit of fury, yelling loudly enough to startle sleeping birds out of their trees ( _‘What am I doing!? What do you think I’m doing!? How did you think I’d react to you suddenly growing horns!?’_ ) and Luffy tries desperately to defend himself in the face of such ire ( _‘But I said I was a demon! I said I’ll show you!’_ ).

The resulting ruckus is impressive enough to cause _Zoro_ to stir, yawn and stretch before he cracks one eye open to take in the noisy scene on the beach.

“...you look like a troll whelp.” Is what the groggy swordsman has to say after a moment of quiet contemplation, then he turns side to go back to sleep.

 

Eventually even Nami finds it in herself to laugh, barely contained giggles turning into exasperated laughter as Luffy tries to pummel his _rude_ first mate.

**Notes for the Chapter:**

> I do love comments, so maybe leave one if ya like?
> 
> For anyone interested; you can find me on tumblr [here.](http://rokudo-no-tsuji.tumblr.com/)


End file.
